Electrolyte level control device for storage batteries



Nov. 24, 1942. J. SANDUSKY 2,302,720

ELECTROLYTE LEVEL CONTROL DEVICE FOR STORAGE BATTERIES Filed April 11, 1941 I INVENTDR- BJMZ ' Patented Nov. 24, 194.2

ELECTROLYTE LEVEL CONTROL DEVICE FOR STORAGE BATTERIES Julius Sandusky, Toronto, Ontario, Canada Application April 11, 1941, Serial No. 388,012

7 Claims. (01. 136-177) This invention relates to an electrolytic level control device for storage batteries such as shown and described in my co-pending patent application 372,348, now Patent No. 2,250,817 granted July 29, 1941. The object of the present invention is to provide means for preventing the float from coming out of the shoulder or battle in which it is mounted; and to improve the operation thereof.

The invention is hereinafter particularly described and is illustrated, by way of example, in the following drawing in which Figure 1 is a top plan view of part of the top of the storage battery showing one filler opening;

Figure 2 a bottom plan view thereof;

Figure 3 a vertical section on the line 33 in Fi ure Figure 4 a horizontal section on the line 4-4 in Figure 2; and

Figure 5 a fragmentary vertical section on the line 5-5 in Figure 1.

In the drawing corresponding parts in the different figures are identified by the same numerals.

The construction of the battery is well known, and therefore only such parts thereof as are relevant to the present invention are indicated. A filling opening I is formed in the top 2 of the battery casing, an outwardly extending boss 3 surrounds the filling opening, the said boss being internally threaded to receive a cap 4 which may be of any suitable construction and which is shown in Figure 3 above the filler opening but is not shown in the other views.

The interior of the boss forms a filling passage which has an extension of less diameter than the diameter of the interior of the boss formed by a tube 3 which extends from a point approximately flush with the top of the casing to a point within the cell below the top of the casing and spaced from the battery plates l2. The filling tube 3 is eccentric to the boss 3 and adjacent one wall thereof leaving a flat shoulder 5 which forms a baflle within the filling passage.

A circular opening 6 is formed in the shoulder. A depending tube 6*? extends from the opening 6 and is of a length substantially equal to the length of the filling tube 3. It will be understood that a closed air space is formed between the bottom of the filling tube 3 and the top of the battery cell and that the normal level of the electrolyte in the cell when filled is approximately at the bottom of said filling tube 3*.

A float 8 is mounted in the baifle opening and water in the filling passage to drop.

closely the sides of the opening. Satisfactory results are obtained if the diameter of the float is about /64" smaller than the diameter of the opening 6 in the shoulder. The length of the float is greater than the length of the baflle tube 6 and the lower end of the float normally rests on the plates l2 although it will be understood that some other stop may be provided for positioning the float 8. When the float is resting on the battery plates the top thereof is normally flush with the surface of the shoulder 5. The float is preferably formed of glass having walls about /64" /64" thick and may be open at the bottom as shown, or if desired, fully enclosed.

In filling the battery, water is poured on the shoulder 5, preferably on top of the float. The water forms a seal over the crevice or space between the float 8 and the opening 6 in the shoulder 5 and prevents the escape of air. The water flows through the filling passage into the cell until the water rises to or slightly above extension 3 of the filling passage, at which point pressure on the float causes it to suddenly rise from the position shown in dotted lines in Figure 3 to the position shown in full lines. This will indicate to the operator that the battery has been filled to the proper level, but if the operator continues pouring, water will rise in the filling passage to the top thereof and will not drop until the float has been pushed down. Pushing the float down breaks the seal in the space between the float and the opening 5 and permits escape of air from the air space beneath the top 2 of the battery casing, causing the Should the float be pushed down and the pouring operation renewed, the float will again rise or jump up and the filling passage will fill up again thus repeating the warning.

It is necessary that a vent be provided to permit the escape of gases which form in the closed air space in the top of the battery. In my aforesaid pending application 372,248 a separate vent or vents have been provided in the shoulder or baffle 6. It has been found that greatly improved results are obtained by eliminating the vents and by forming an opening 6 in the side of the tube 5 just below the opening 6 in the shoulder 5. The opening 6 is preferably in the form of a slot extending from the bottom of the tube 6 to a point approximately 1 below the upper edge of the opening 6 in the shoulder 5. This permits the passage of air from the air space in the top of the battery into the interior of the extends down through the baflle tube 6 fitting tube from whence it y P p through the 2 aaoa'mo space or crevice between the float O and the inside of the opening 8.

The diameter of the tube 6' is enlarged below the shoulder 8 and a plurality of vertical ribs II are formed in the inside or the enlarged portion of the tube, two of said ribs being located on either side of the opening i", and a third being located substantially opposite to the said opening 8". These ribs are substantially the same thickness as the difference between the radius oi the enlarged portion of the tube I and the radius of the opening 0, that is to say a circle drawn to touch the outer faces ofthe ribs ll would have the same diameter as the diameter of the opening 6. These ribs guide the float and retain it in a substantially vertical position and at the same time reduce the friction between the float and the tube so that it is more sensitive to the air and water pressure which causes it to rise in the tube.

The float rises with considerable velocity and may jump out of the opening in the shoulder. To avoid this difliculty I have provided on the float a tip or projection 8 adapted to fit into a groove 9 in the opening 6 and the wall of the tube Ii above the enlarged portion thereof. When the float is inserted in the opening the projection 8 is placed in register with the groove and is pressed down until the projection 8 passes the flange or shoulder I3 formed between the enlarged portion of the tube and the portion which is smaller or of less diameter, and they float is then turned so that the projection is out of register with the groove 9 and will'engage the said flange or shoulder when the float rises, thus preventing it from coming out. The groove 9 is so small that it does not materially affect the venting of the battery, particularly as it is located opposite the slot 6.

The construction herein described has the advantage that if the cap is not placed on the cell of the battery very little evaporation will take place and the acid in the battery will not spill out unless the battery is subjected to unusual agitation. For instance, if the battery is used in a motor car even with the cap removed, under ordinary operationof the car the acid will not spill out. For use in aeroplanes, when the battery may sometimes be inverted, the cap 4 i provided with a tube 4 surrounding the usual vent 4 and extending below the top of the cap. The restricted portion 3 of the inlet passage is lo cated as above described to one side of the center of the filling passage and to one side of the central vent 4, so that if the battery is inverted and there is a. flow of water outwardly through the filling passage it will flow into the space around the tube 4 and not into the tube. The flow will be very slight since air will be trapped and will only escape very slowly through the vent 4, so that unless the battery remains inverted for a considerable length of time, only a small amount of the acid will collect around the tube 4 and when the battery is returned to its normal upright position, this will flow back into the battery proper.

The battery is filled by pouring water on the shoulder 5 and over the float 8. The water seals the space or crevice between the'opening 6 and the float 8 and flows down through the restricted portion 3 of the filling opening into the battery until the water in the battery rises to the lower edge or the filling opening, when water and air pressure on the float 8 causes it to rise rapidly indicating that the battery is filled. The float willremaininaraisedposltlonaslongaswater is poured on it and !or some time thereafter until the seal breaks or until it is pushed down, and if the filling operation is repeated the float will immediately jump up again. when the battery is filled the operator will place the cap on the filling opening and screw it down, thus pushing the float down to its normal position. If despite the warning given by thefloat the operator should continue to pour water in the battery, pushing the float down to permit the water in the filling passage to flow into the battery, it has been found that the battery cannot by any means he filled above V2" to from the top of the battery.

Thus, there is a double indication that the battery is fllled, namely the rising of the float and the rising of the water in the filling tube. The operation of the float is very sensitive, but it will not drop as long as water is poured on and remains up for an appreciable time after pouring has stopped. Ample ventilation is provided through the opening in the bane tube and between the float and sides of the opening in the shoulder, and the float 1s eifectively prevented from coming out of the opening in the shoulder.

Thus a fool-proof positive indication of the level of the electrolyte is obtained.

Although the invention has been described in some detail, it will be understood that it is not limited to the details of construction described except as specified in the appended claims.

What I claim as my invention is:

1. In an electrolytic level control device for storage batteries; cell having a filling opening in the top thereof; a filling passage formed by walls which extend downwardly from said opening into the cell and form a closed air space within the top of the cell; a shoulder in said passage having a horizontal opening therein coinmunicatlng with the interior of the cell, the said shoulder having a vertical groove in the side wall of the opening; and a float in the opening in said shoulder closing the said opening, said float fitting the sides of the opening so closely that when water is poured on the shoulder a seal will form over the space or crevice between the float and the sides of the opening to prevent the escape of air from within the cell, said float having a projection on the side thereof adapted to pass through the groove in the shoulder and engage the underside of the opening to retain the float therein.

2. In an electrolytic level control device for storage batteries; a cell-having a filling opening in the top thereof; a filling passage formed by walls which extend downwardly from said opening into the cell and form a closed air space within the top of the cell; a shoulder in said passage having a horizontal opening therein communicating with the interior of the cell; a tube in registry with the opening in the shoulder extending from said shoulder into the cell, said tube having an aperture in the side thereof form'- ing a communication between the interior of the cell and the interior of the'tube adjacent to but below the shoulder; and an elongated float in said tube, closing the said opening in the shoulder, said float fitting the sides of the opening in the shoulder so closely that when water is poured on the shoulder a seal will form over the space or crevice between the float and the sides of the opening to prevent the escape of air from within the cell. I

3. In an electrolytic level control device for cating'with the interior of the cell; a tube in s registry with the opening in the shoulder extending from said shoulder into the cell, said tube having a slot on the side thereof extending from the bottom of the tube to a point adjacent to but below the shoulder and forming a communication between the interior ofthe cell and the interior of the tube; and an elongated float in said tube, closing the said opening in the shoulder, said float fitting the sides of theopening in the shoulder so closely that when water is poured on the shoulder a seal will form over the space or crevice between the float and the sides of the opening to prevent the escape of airfrom within the cell. v

4. In an electrolytic level control device for storage batteries; a cell having a filling opening inthe" top thereof; a filling passage formed by' walls which extend downwardly from said open ing into the cell and form a closed air space within the top of the cell; a shoulder in said passage having a horizontal opening therein communicating with the interior of the cell; a tube in registry with the opening in the shoulder extending from said shoulder into the cell, the diameter of said tube below the shoulder being larger than the diameter of the opening in the shoulder; and an elongated float in said tube, closing the said opening in the shoulder, said float fitting the sides of the opening in the shoulder so closely that when water is poured on the shoulder a seal will form over the space or crevice between the float and the sides of the opening to prevent the escape of air from within the cell,

5. In an electrolytic level control device for storage batteries; a cell having a filling opening in the top thereof; a filling passage formed by walls which extend downwardly from said opening into the cell and form a closed air space to guide the float; and an elongated float in said tube, closing the said opening in the shoulder, said float fitting the sides of the opening in the shoulder so closely that when water is poured on the shoulder a seal will form over the space or crevice between the float and the sides 01' the opening to prevent the escape of air from within the cell,

6. In an electrolytic level control device for storage batteries; a cell having a filling opening in the top thereof; a filling passage formed by walls which extend downwardly from said opening into the cell and form a closed air space within the top of the cell; a shoulder in said passage having a horizontal opening therein communicating with the interior of the cell; a tube in registry with 'the opening in the shoulder extending from said shoulder into the cell, said tube having a slot in the side thereof extending from the bottom of the tube to a point adjacent but belowthe shoulder and forming a communication between the interior of the cell and the interior of the tube, the diameter of said tube below the shoulder being larger than the diameter of the opening in the shoulder, and said tube having a longitudinal internal rib on either side of said slot; and an elongated float in said tube, closing the-said opening in the shoulder, said float fitting the sides or the opening in the shoulder so closelythat when water is poured on the shoulder a-seal will form over the space or crevice between the float and the sides of the opening to prevent the escape of air from within the cell.

'7. In an electrolytic level control device for storage batteries; a cell having a filling opening in the top thereof; a -filling passage formed by walls which extend downwardly from said open- 7 ing into the cell and form a closed air space within the top of the cell; a shoulder in said passage having a horizontal opening therein com-' municating with the interior of the cell; a tube in registry with the opening in the shoulder extending from said shoulder into the cell, the diameter of said tube below the opening in the shoulder being larger than the diameter of the opening in the shoulder, and said opening and tube above the enlarged portion having a vertical groove in the side thereof; and an elongated float in said tube, closing the said opening in the shoulder, said float fitting the sides of the opening in the shoulder so closely that when water is poured on the shoulder a seal will form over the space or crevice between the float and the sides of the opening to prevent the escape of air from within the cell, said float having a projection on the side thereof adapted to pass through the groove in the opening in the shoulder and the tube and engage the underside of the portion of the tube having the smaller diameter to retain the float therein.

JULIUS BANDUSKY. 

